Most Ecosystems on Earth Rely on Sunlight as the Primary

question 12

Multiple Choice

Most ecosystems on Earth rely on sunlight as the primary energy source for the synthesis of organic compounds that living organisms need. Sunlight does not penetrate deep enough in the ocean to provide energy for organisms living near hydrothermal vents. How can these densely populated communities survive without energy from the sun?

• A) chemoheterotrophic bacteria convert organic compounds into carbon dioxide which is used by other organisms as an energy source
• B) chemoautotrophic bacteria harvest chemical energy from hydrogen sulfide and then provide the basis of food for the vent communities
• C) chemoheterotrophic bacteria harvest chemical energy from hydrogen sulfide and then provide the basis of food for the vent communities
• D) chemoautotrophic bacteria fix nitrogen which then is used as a source of energy for other organisms

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Definitions:

Chemicals

Substances used in the production of goods or services, often characterized by their compositions and potential reactions.

Encumbrances

Legal claims or liens on property or assets that can affect the ability to transfer ownership or limit its use.

Chain of Title

The sequence of historical transfers of title to a property, tracing ownership from the current owner back to the original source of the property.

Zoning Ordinances

Laws that define how property in specific geographic zones can be used.